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    <title>Document</title>
    <style>
        /* 现在我想让p元素且class为star的标签文字为红色, 可以这么写 */
        p.star{
            color: red;
        }

        /* 交集选择器也可以这么用 */
        .star.test{
            color: green;
        }
    </style>
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<body>
    <h2 class="rich">土豪张三</h2>
    <h2 class="star test">明星李四</h2>

    <hr>

    <p class="star">小狗旺财</p>
    <p class="animal">小猪佩奇</p>
</body>
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